text: The ICRP states "Radionuclides incorporated in the human body irradiate the tissues over time periods determined by their physical half-life and their biological retention
  within the body. Thus they may give rise to doses to body tissues for many months or years after the intake. The need to regulate exposures to radionuclides and the
  accumulation of radiation dose over extended periods of time has led to the definition of committed dose quantities".
  The ICRP defines two dose quantities for individual committed dose.
  * Committed equivalent dose is the time integral of the equivalent dose rate in a particular tissue or organ that will be received by an individual following intake of radioactive material into the body by a Reference Person, where t is the integration time in years. This refers specifically to the dose in a specific tissue or organ, in the similar way to external equivalent dose.
  * Committed effective dose, is the sum of the products of the committed organ or tissue equivalent doses and the appropriate tissue weighting factors W, where t is the integration time in years following the intake. The commitment period is taken to be 50 years for adults, and to age 70 years for children. This refers specifically to the dose to the whole body, in the similar way to external effective dose. The committed effective dose is used to demonstrate compliance with dose limits and is entered into the "dose of record" for occupational exposures used for recording, reporting and retrospective demonstration of compliance with regulatory dose limits.
  The ICRP further states "For internal exposure, committed effective doses are generally determined from an assessment of the intakes of radionuclides from bioassay measurements or other quantities (e.g., activity retained in the body or in daily excreta). The radiation dose is determined from the intake using recommended dose coefficients".